drm/virtgpu: initialise fbdev after getting initial display info

This should avoid issues with the fbdev path trying to render
before we've gotten the display info.

Signed-off-by: Dave Airlie <airlied@redhat.com>

[ kraxel: wait for display-info reply ]

Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>

3 files changed, 6 insertions, 1 deletions

diff --git a/drivers/gpu/drm/virtio/virtgpu_drv.h b/drivers/gpu/drm/virtio/virtgpu_drv.h
index e5a2c092460b..ff8de3d6f0b2 100644
--- a/drivers/gpu/drm/virtio/virtgpu_drv.h
+++ b/drivers/gpu/drm/virtio/virtgpu_drv.h
@@ -171,6 +171,7 @@ struct virtio_gpu_device {
         wait_queue_head_t resp_wq;
         /* current display info */
         spinlock_t display_info_lock;
+        bool display_info_pending;
 
         struct virtio_gpu_fence_driver fence_drv;
 
diff --git a/drivers/gpu/drm/virtio/virtgpu_kms.c b/drivers/gpu/drm/virtio/virtgpu_kms.c
index 132405f15389..782766c00d70 100644
--- a/drivers/gpu/drm/virtio/virtgpu_kms.c
+++ b/drivers/gpu/drm/virtio/virtgpu_kms.c
@@ -137,9 +137,11 @@ int virtio_gpu_driver_load(struct drm_device *dev, unsigned long flags)
         virtio_device_ready(vgdev->vdev);
         vgdev->vqs_ready = true;
 
+        virtio_gpu_cmd_get_display_info(vgdev);
+        wait_event_timeout(vgdev->resp_wq, !vgdev->display_info_pending,
+                           5 * HZ);
         if (virtio_gpu_fbdev)
                 virtio_gpu_fbdev_init(vgdev);
-        virtio_gpu_cmd_get_display_info(vgdev);
 
         return 0;
 
diff --git a/drivers/gpu/drm/virtio/virtgpu_vq.c b/drivers/gpu/drm/virtio/virtgpu_vq.c
index 8fa6513eb3bc..c5067926401f 100644
--- a/drivers/gpu/drm/virtio/virtgpu_vq.c
+++ b/drivers/gpu/drm/virtio/virtgpu_vq.c
@@ -534,6 +534,7 @@ static void virtio_gpu_cmd_get_display_info_cb(struct virtio_gpu_device *vgdev,
                 }
         }
 
+        vgdev->display_info_pending = false;
         spin_unlock(&vgdev->display_info_lock);
         wake_up(&vgdev->resp_wq);
 
@@ -558,6 +559,7 @@ int virtio_gpu_cmd_get_display_info(struct virtio_gpu_device *vgdev)
                  resp_buf);
         memset(cmd_p, 0, sizeof(*cmd_p));
 
+        vgdev->display_info_pending = true;
         cmd_p->type = cpu_to_le32(VIRTIO_GPU_CMD_GET_DISPLAY_INFO);
         virtio_gpu_queue_ctrl_buffer(vgdev, vbuf);
         return 0;